A silicon semiconductor is a material that has been conventionally investigated for materials for thin-film transistor (TFT) and solar cell.
In formation of a pattern of a silicon thin film used for applications such as integrated circuits and thin-film transistors, a silicon film is generally formed through a vacuum process such as a CVD process and others. Since in a device for this formation, the vacuum process is used, the device is required to be large-scale. Further, there are problems in which handling is difficult since a raw material is a gas.
In order to solve the problems, there is a procedure in which the silane polymer is dissolved in an organic solvent, applied to a substrate, baked, and dehydrogenated to form a silicon film.
For example, a composition containing an oligosilane or polysilane consisting of hydrogen and silicon and/or germanium and having a molecular weight of 450 to 2,300, which, after coating and printing the composition to form an oligo- or polysilane film, and then curing, forms an amorphous, hydrogenated semiconductor film having a carbon content of 0.1% by atom or less is disclosed (Patent Document 1). Synthesis of polysilane using a heterogeneous catalyst consisting of transition metal elements of Groups 7 to 12 or substrate-anchored derivatives thereof is described.
A method for producing a silane polymer including irradiating a photopolymerizable silane compound with a light having a wavelength of 405 nm to produce a silane polymer having a weight average molecular weight that is measured by gel permeation chromatography in terms of polystyrene of 800 to 5,000 is disclosed (Patent Document 2).
A composition containing a cross-linked polymer containing: (a) linear chains of atoms that are cross-linked to each other via a direct bond between atoms from different chains, wherein the atoms are independently selected from the group consisting of a Si atom and a Ge atom; and (b) side chains R as R groups that are directly bonded to the atoms in the chain to complete the valence of the atoms in the chain, provided that when all the R groups are independently selected from the group consisting of hydrogen, halogen, an aromatic hydrocarbyl group, and a substituted aromatic hydrocarbyl group, the degree of cross-linking includes about 10% or less of the linear chain of atoms is disclosed (Patent Document 3).
A method for forming an amorphous silicon-deposited film on a support placed in a deposition chamber by introducing a cyclic silane compound of general formula (SiH2)n (n=4, 5, or 6) in a gas state with a carrier gas into the deposition chamber, and applying heat energy under normal pressure is disclosed (Patent Document 4).
However, the average molecular weights of the polysilane and the silicon-containing polymer are small. Therefore, there are problems in which the crystallinity of dehydrogenated polysilane to be obtained by baking is low and high conductivity is not achieved.